Erick strengthened to a hurricane off of southern Mexico Saturday, threatening to dump heavy rain as it skirts the country's Pacific coast.
The presence of the Category 1 hurricane forced the closure of the seaport of Manzanillo, Mexico's biggest container port.
The U.S. National Hurricane Center in Miami said Erick became a hurricane as its maximum sustained winds grew to around 110 kph.
The hurricane was centred about 145 kilometres south of Manzanillo and was moving northwest at 15 kph, on a track roughly parallel to the coast for the states of Guerrero, Colima and Jalisco.
A hurricane watch was declared for Punta San Telmo to Cabo Corrientes, and a tropical storm warning was in effect from the resort of Zihuatanejo westward to Cabo Corrientes.
Gabriel Rivas, a meteorologist at the Manzanillo Port Authority, said the port was closed late Friday as a precaution, but no rain or high winds had yet been reported in the area.
In neighbouring Jalisco state, civil defence officer Leonel Hernandez said authorities in coastal communities were meeting to plan preparations for the hurricane, but that skies in the Jalisco coastal community of Cihuatlan were still clear.
Forecasters predict a northwest to west-northwest track over the next few days but say the storm should remain offshore. Rain accumulations from 76 to 127 millimetres are expected. Forecasters warn of flash floods.